# How to check if a number is a perfect square in Python

Let’s learn how to check if a number is a perfect square number in Python. Here we need to use Math module of python to check the number.

## Check if a number is a perfect square or not in Python

Perfect Square Number: When a number is expressed as the product of two equal numbers, then that number is said to be a perfect square number. For example:- 25 is a perfect square as it can be expressed as a product of 5*5, 81 is also a perfect square as it can be expressed as a product of 9*9.

List of perfect square numbers between 1 to 100 are :-

• 1 = 1*1
• 4 = 2*2
• 9 = 3*3
• 16 = 4*4
• 25 = 5*5
• 36 = 6*6
• 49 = 7*7
• 64 = 8*8
• 91 = 9*9
• 100 = 10*10

Steps to check perfect square number in Python:

• Step 1:- Import the math module.
• Step 2:- Find the square root of the given number using the math.sqrt(), and store that value in a variable. ( You can learn: Mathematical Functions in Python )
• Step 3:- Subtract the value obtained after taking the floor/round of the value stored in the variable from the given original number.
• Step 4:- If the final result is equal to ZERO, then the given number is a perfect square number.

### Python program to check if a number is perfect square or not

```import math
n=121
x=math.sqrt(n)
y=(x-math.floor(x))
print("Difference between the square root of a number and the given number is",y)
if(y==0):
print("Perfect Square Number")
else:
print("Not Perfect Square Number")```

Output:

```Difference between the square root of a number and the given number is 0.0

Perfect Square Number```

#### Another example where n = 127

```import math
n=127
x=math.sqrt(n)
y=(x-math.floor(x))
print("Difference between the square root of a number and the given number is",y)
if(y==0):
print("Perfect Square Number")
else:
print("Not Perfect Square Number")```

Output:

```Difference between the square root of a number and the given number is 0.26942766958464404

Not Perfect Square Number```